Potential source of cerebral embolism in migraine with aura: a transcranial Doppler study

The Role of Cardiac and Pulmonary Pathology in Migraine: A Hypothesis

From observation of recent data linking migraine with right-to-left shunts and by analogy with the etiologies of decompression illness, we postulate that cardiac and pulmonary pathology can have an important effect on the cranial final common pathway that generates attacks of migraine. One possible mechanism is associated with a significant right-to-left shunt, which is usually through a persistent foramen ovale, but is sometime through a pulmonary shunt. This allows a venous agent, possibly 5-hydroxytryptamine, to bypass the lung filter. Migraine can occur when there is no shunt if similar agents are liberated in the left heart beyond the lung filter, possibly by platelet activation. Migraine could also occur if the venous agents are produced in such large amounts that they overwhelm the pulmonary filter or are unaffected by passage through the lungs. In some individuals migraine may be unrelated to blood-borne triggers.

Migraines Linked to Intrapulmonary Right-to-Left Shunt

OBJECTIVE

To determine if there is an association between migraines and intrapulmonary right-to-left shunt.

BACKGROUND

Several studies have described an association between migraines and intracardiac right-to-left shunt.

METHODS

Patients with hereditary hemorrhagic telangiectasia (HHT) were retrospectively recruited from the Toronto Hereditary Hemorrhagic Telangiectasia Center Clinical Database. All patients had been prospectively, systematically asked about a history of migraines and systematically screened for pulmonary and cerebral arteriovenous malformations (AVMs). All patients with a definite diagnosis of HHT, assessed during a 2-year period (February 1997 to April 1999), were included. Univariate analyses and logistic regression were performed, for migraine as the dependent variable and the following independent variables: age, sex, pulmonary AVMs, and cerebral AVMs.

RESULTS

Of the 200 patients assessed during the 2-year period, 124 (62%) had a definite diagnosis of HHT and were included in the analysis. Eighty (65%) were females. Forty-seven (38%) of the HHT patients had a history of migraine, of whom 38 (81%) had migraine with aura. The prevalence of migraine was greater in patients with pulmonary AVMs (46%) compared to patients without pulmonary AVMs (33%), OR = 1.7 (0.8 to 3.6), though this did not reach statistical significance (P = .14). Pulmonary AVMs were significantly associated with migraine (OR = 2.4, 95% CI = 1.1 to 5.5, P = .04), after adjustment for age and sex, using logistic regression.

CONCLUSIONS

There is a significant association between intrapulmonary right-to-left shunt and migraine.

Long-term efficacy of transcatheter patent foramen ovale closure on migraine headache with aura and recurrent stroke

OBJECTIVES

To assess the long-term results of transcatheter patent foramen ovale (PFO) closure on migraine headache with aura (MHA) and on the risk of recurrent stroke.

BACKGROUND

Transcatheter PFO closure is associated with an early improvement of MHA, and a reduction or the risk of recurrent cerebral ischemia, but the long-term outcome after the procedure is unknown.

METHODS

We analyzed follow-up data of 38 consecutive patients who had undergone transcatheter PFO closure at our institution because of cryptogenic stroke and had been followed-up for at least 3 years after the procedure. Mean age at closure was 43 +/- 13 years. Thirteen patients (34%) had a diagnosis of MHA made by the primary care physician or the referring neurologist. Migraine disability assessment questionnaire (MIDAS) was used to assess MHA incidence and severity.

RESULTS

After a mean follow-up of 4.8 +/- 1.4 years, two patients had a recurrent stroke (13 and 15 months after the procedure, respectively). Recurrence rate 5 years after the procedure was 5.3%. After 4.9 +/- 1.4 years from the intervention, 12/13 patients (92%, 95% CI 65-99%) had complete resolution in their MHA. Overall, MIDAS score decreased significantly (38.6 +/- 26.3 vs. 4.4 +/- 5.1, P < 0.0001) after the procedure. One patient did not report any improvement of MHA after transcatheter PFO closure, whereas one patient reported a severe relapse of MHA about 1 year after PFO closure. Freedom from recurrent MHA 5 years after the procedure was 85% (95% CI 57-97%).

CONCLUSIONS

The rate of recurrent cerebral ischemia and recurrent MHA seems to be low at long-term follow-up after transcatheter PFO closure. Recurrent cerebral ischemia and relapse of MHA seem to be confined to the first 15 months after the procedure.

Transcatheter patent foramen ovale closure using the premere PFO occlusion system

OBJECTIVES

To evaluate the safety and efficacy profile of the new Premere patent foramen ovale (PFO) occlusion system.

BACKGROUND

Several different devices have been used so far for transcatheter PFO closure but no data has been published so far on the efficacy and safety of the Premere PFO occlusion system.

METHODS

Since September 2005, 15 patients (seven males, eight females; mean age 51.2 +/- 10.8 years) at our institution underwent transcatheter PFO closure because of cryptogenic stroke, using the Premere PFO occlusion system. The procedure was performed under fluoroscopic and transesophageal echocardiographic (TEE) guidance in all patients. Seven patients (47%) had an associated atrial septal aneurysm and two patients had had >1 stroke. Five patients (33%) had an associated thrombophilia, whereas three patients (20%) had a diagnosis of migraine headache with aura, by the referring neurologist. Residual shunt was assessed immediately after and 1 month (only in 11 patients) after the procedure by both transcranial Doppler and TEE.

RESULTS

Premere PFO devices could be implanted in all patients (20 mm size in seven patients, 25 mm size in eight). Fluoroscopy time was 7.3 +/- 1.9 and procedural time was 11 +/- 3 min (range 7-17 min), reflecting our initial learning curve with this device. No complication occurred during the procedure or at follow-up. A residual shunt was noted immediately after the procedure in eight patients (53%) and at 1 month in 4/11 patients (36%). Residual shunt was mild in all patients. After a median follow-up of 4.2 months (0.2-5.8 months), no patient had a recurrent stroke. All patients with migraine headache with aura had resolution of symptoms.

CONCLUSIONS

Our preliminary experience with the Premere PFO occlusion system shows that this device is safe and effective.

Shunt-associated migraine responds favorably to atrial septal repair: a case-control study

BACKGROUND AND PURPOSE

Transcatheter closure of patent foramen ovale (PFO) has been reported to improve migraine in patients with cerebrovascular disorders in noncontrolled studies. The aim of the study was to compare the course of migraine assessed prospectively over a 12-month period in symptomatic (for cerebrovascular disease) and asymptomatic patients undergoing PFO closure and in patients with PFO treated medically.

METHODS

Twenty-three stroke symptomatic (SS; 39+/-10 years of age; males/females [M/F] 5/18) and 27 stroke asymptomatic (SA; 40+/-12 years of age; M/F 5/22) patients with migraine underwent PFO closure. Twenty-seven patients with migraine and PFO (controls [CTRLS]; 36+/-11 years of age; M/F 4/23) were followed up medically. Migraine severity was assessed at baseline with a scale that takes into account the frequency, duration, and intensity of the attacks and the occurrence of aura (score range 0 to 10). Six months later, the patients were given a structured diary to annotate monthly with the same scale the characteristics of the attacks for the next 6 months. By the end of 1 year, the migraine score was averaged for the last 6 months.

RESULTS

Baseline severity of migraine did not differ between groups (6.3 to 6.1 and 6.7 in SS, SA, and CTRLS groups, respectively). At the 1-year assessment, the overall migraine score had significantly improved by 3.7 and 2.8 points in SS and SA, respectively (P<0.001 on repeated-measure ANOVA), whereas it had nonsignificantly worsened by 0.1 points in CTRLS. Multiple linear regression analysis showed that the improvement in SS and SA was independent of migraine type, age, and cerebrovascular risk factors. Twenty-one of 21 patients with migraine with aura in the CTRLS group still had aura at the end of follow-up, whereas only 3 of 14 among SA and 4 of 19 among SS continued to have migraine preceded by aura (P<0.0001 on Fisher exact test).

CONCLUSIONS

Compared with medical treatment, closure of PFO brings about a significant overall improvement in migraine. This seems to occur irrespective of migraine type and of previous cerebrovascular disease. In addition to the overall improvement, in migraine with aura, the occurrence of aura is dramatically reduced.

The management of patients with patent foramen ovale and stroke

The management of patients with patent foramen ovale (PFO) and stroke remains uncertain. What is known is that PFO is a very common finding in the general population. The risk of initial and recurrent stroke in individuals with PFO is relatively low. With the advent of transesophageal echocardiography, PFO is more commonly being diagnosed. There are insufficient data to support a benefit of warfarin over aspirin in preventing recurrent stroke in most patients with PFO. In those with PFO and a history of a procoagulant state or deep venous thrombosis, anticoagulation may be indicated after weighing the risks of anticoagulation against potential benefits in preventing recurrent stroke. PFO closure does not guarantee the prevention of future stroke and should be addressed case by case, with consideration of patients for entry into ongoing clinical trials of safety, efficacy, and durability.

Defeitos de septo atrial como fator de risco para migrânea: um estudo de caso controle

Para determinar a magnitude da associação entre defeitos de septo atrial (DSA) e migrânea avaliamos 101 indivíduos submetidos ao ecocardiograma transesofágico (ETE). Eles foram questionados sobre a presença de cefaléia. Migrânea foi diagnosticada segundo os critérios da Sociedade Internacional para Estudo das Cefaléias segunda edição. Pareamos 1:1 em portadores de DSA (casos) e indivíduos com septo atrial normal (controles). Calculamos frequência de migrânea e de aura e a ocorrência de mais de três crises no último mês. Analisamos as diferenças pelo teste do qui-quadrado. Pareamos 34 casos e controles. Média etária 38,7(±11,2) e 38,9(±11,17) sendo 82,4% mulheres. Migrânea ocorreu em 79,4% dos casos e 55,9% dos controles (or= 4,3 ic 95% = 1,048 - 8,89) (p= 0,038). Aura ocorreu em 65,1%(casos) e 40%(controles). Em 76,7% casos e 60% dos controles ocorreram mais de três crises no último mês. DSA se constituiu fator de risco para migrânea com aura na amostra estudada. DSA parece aumentar a freqüência de crises de migrânea.

Migraine with aura related to closure of atrial septal defects

A 27-year-old woman had a history of migraine with aura (MWA) since aged 13 years with mostly two attacks per year. After transcutaneous closure of a secundum atrial septal defect (ASD) she suffered from almost daily recurring migraine attacks with prolonged aura symptoms. Exacerbation and new appearance of migraine attacks with aura after transcutaneous closure of ASD have been described previously.

Migraine and white matter hyperintensities

Patients with migraine are at increased risk for white matter hyperintensities detected on magnetic resonance imaging. The presence of nonspecific white matter hyperintensities may cause uncertainty for physicians and anxiety for patients. The pathophysiology and long-term consequences of these lesions are unknown. Occasionally, white matter lesions in a migraineur may indicate an underlying disease such as cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), mitochondrial encephalopathy with lactic acidosis and stroke-like episodes (MELAS), or central nervous system vasculitis. The ability to distinguish between nonspecific and disease-specific patterns of white matter hyperintensities in migraine sufferers is important for the practicing clinician.

Patent foramen ovale: current pathology, pathophysiology, and clinical status

Patent foramen ovale (PFO) is experiencing increased clinical interest as a congenital cardiac lesion persisting into adulthood. It is implicated in several serious clinical syndromes, including stroke, myocardial infarction, and systemic embolism. The PFO is now amenable to percutaneous interventional therapies, and multiple novel technologies are either available or under development for lesion closure. The PFO should be better understood to take advantage of emerging percutaneous treatment options. This paper reviews PFO anatomy, pathology, pathophysiology, and clinical impact and discusses current therapeutic options.

Relation between migraine and stroke

A complex bidirectional relation between migraine, mostly migraine with aura (MA), and ischaemic stroke is known. A cerebral infarction can occur during a MA, and MA is a risk factor for ischaemic stroke, particularly in young women. Conversely, cerebral ischaemia can induce MA. Both ischaemic stroke and MA might be consequences of many underlying vascular disorders. Despite the relation between migraine and stroke, migraine as a primary headache disorder is mostly benign.

The risk of stroke in patients with migraine and implications for migraine management

Assessing the risk of stroke in persons with migraine is complicated by the intricate relationship between these two conditions. Both migraine and stroke are common and co-morbidity may, in some cases, be coincidental. Given the overlap of clinical symptoms in stroke and migraine, each condition may also mimic the other. Numerous studies have, however, shown that migraine is an independent risk factor for stroke both during, and remote from, the migraine attack. Women of childbearing age and those with aura are at greatest risk of migraine-related stroke. Additional risk of stroke in migraineurs occurs in those using oral contraceptive pills and who smoke cigarettes. Elevated blood pressure, an important stroke risk factor, is less common in migraineurs. Acquired antiphospholipid antibodies, not clearly a cause of migraine per se, may raise the risk of infarction in migraineurs. Hereditary conditions, including CADASIL (cerebral autosomal dominant arteriopathy with sub-cortical infarcts and leukoencephalopathy), MELAS (mitochondrial myopathy, encephalopathy, lactacidosis and stroke) and hereditary haemorrhagic telangiectasia, appear to predispose to both migraine and stroke. Purported mechanisms for migraine-associated stroke include involvement of the vasculature (including vasospasm, arterial dissection and small vessel arteriopathy), hypercoagulability (elevated von Willebrand Factor, platelet activation) and elevated risk of cardioembolism (patent foramen ovale, atrial septal aneurysm). Triptans and ergotamines, used to treat acute migraine attacks, appear to be safe in low-risk populations. These medications should be avoided in persons with haemiplegic migraine, basilar migraine, vascular risk factor and prior cerebral or cardiac ischaemia.

Clopidogrel reduces migraine with aura after transcatheter closure of persistent foramen ovale and atrial septal defects

OBJECTIVE

To report the clinical events leading to alteration of an anticoagulation regimen for patients undergoing transcatheter closure of an atrial shunt and how this affected migraine symptoms after the closure procedure.

METHOD

Audit of a change of anticoagulant regimen.

RESULTS

In the first few weeks after a closure procedure migraine frequency and severity increased despite treatment with aspirin for six months in 71 patients. Severe attacks of migraine with aura, including status migrainosus, in the first few weeks after transcatheter closure were terminated by addition of clopidogrel to aspirin treatment. Therefore, the anticoagulant regimen was changed with addition of clopidogrel for the first month after the closure procedure (90 procedures in 89 patients). Fewer patients had migraine with aura in the first month after transcatheter closure when taking the combination of clopidogrel and aspirin compared with aspirin alone (11 of 90 (12.2%) v 30 of 71 (42.3%), p < 0.001). Episodes of migraine with aura were more severe and more frequent in patients taking aspirin alone.

CONCLUSION

The combination of clopidogrel for four weeks and aspirin for six months is superior to aspirin alone for six months for preventing migraine with aura after transcatheter closure of an atrial shunt. This beneficial effect of a powerful inhibitor of platelet aggregation suggests that platelets may have a role in pathogenesis of migraine. This may be because of an effect on serotonin stores. Whether clopidogrel has a role in treatment of migraine in other clinical situations requires investigation.

A mystery featuring right-to-left shunting despite normal intracardiac pressure

The cause of right-to-left atrial shunting despite normal intracardiac pressures and normal or near-normal pulmonary function through a patent foramen ovale has still not been completely clarified. It is probably responsible for several linked diseases, such as paradoxical embolism, platypnea-orthodeoxia syndrome, migraine with aura, transient global amnesia, and decompression sickness in sport divers. Despite modern diagnostic methods, the underlying anatomophysiologic and pathogenic mechanisms of right-to-left atrial shunting without abnormal intracardiac pressures remain a matter of debate and controversy. Holistically speaking, a return to a direct study of embryology, gross anatomy, and physiology may help us elucidate the real mechanism of this paradoxical shunting.

Patent foramen ovale: paradoxical connection to migraine and stroke

PURPOSE OF REVIEW

In this article we aim to elucidate the relationship between patent foramen ovale, cryptogenic stroke and migraine.

RECENT FINDINGS

Small observational and case-control studies indicate that patients with cryptogenic stroke have a higher incidence of patent foramen ovale. Prospective trials could not show a higher stroke recurrence risk with isolated patent foramen ovale. The combination of patent foramen ovale and atrial septal aneurysm might carry a higher recurrence risk. Secondary prevention with acetylsalicylic acid is as effective as oral anticoagulation, but carries a lower bleeding risk. Whether patent foramen ovale closure prevents recurrent strokes is under investigation. Case-control studies and retrospective analyses indicate comorbidity between patent foramen ovale and migraine, in particular migraine with aura. Recent retrospective studies indicate a reduction in migraine frequency after patent foramen ovale closure (intended for stroke prevention). These studies, however, have major methodological limitations. Therefore patent foramen ovale closure cannot be recommended for the prevention of migraine with aura.

SUMMARY

At present routine percutaneous closure of isolated patent foramen ovale cannot be recommended for patients with cryptogenic stroke. Patent foramen ovale closure should not be used for the prevention of migraine.

The persistent foramen ovale and migraine

There is association between migraine, particularly migraine with aura, and large persistent foramen ovale (PFO) and other right-to-left shunts. Migraine is often improved by closure of a PFO in patients who have a large shunt. Inheritance of migraine is linked to the inheritance of large atrial shunts in some families. The data indicate that in some patients PFOs play a causal role in migraine with aura. These observations may also improve understanding of the etiology of migraine in patients who do not have a shunt.

Intense Migraines Secondary to Percutaneous Closure of Atrial Septal Defects

In this study we evaluated the development of migraine after percutaneous closure of atrial septal defect. An abrupt and excruciating form of migraine developed shortly after shunt closure in 5 of 13 consecutive patients undergoing this procedure. A dramatic relief of pain was achieved almost instantaneously after administration of 300 mg of clopidogrel.

Patent foramen ovale: The never-ending story

Several uncontrolled studies suggested a relationship between patent foramen ovale (PFO) and stroke. But recent data indicate that previous studies may overestimate the association between PFO and stroke. First, among patients who have had a cryptogenic stroke under treatment (with either warfarin or aspirin), the main data from the French PFO/atrial septal aneurysm (ASA) and PICSS (Patent Foramen Ovale in Cryptogenic Stroke Study), analyzed separately and in combination, indicate that PFO alone does not announce a significantly increased risk of recurrent stroke or death. But a small increase or decrease in risk cannot be excluded by this meta-analysis. Second, the data concerning the association between PFO and ASA are not clear and variable: the French PFO/ASA study found a significantly increased risk of recurrent stroke in patients with cryptogenic stroke and an association between PFO and ASA when treated medically. In contrast, PICSS found no association between the combined PFO-ASA with stroke or death, but the two populations had meaningful differences. Patients in the PICSS were much older than those in the French PFO/ASA study and had more risk factors for stroke, such as hypertension, diabetes, and history of prior stroke. Third, there were inadequate data to conclude about ASA alone. Possible practice recommendations could come from this meta-analysis: the evidence indicates that the risk of recurrent stroke or death is not different for patients with a PFO who underwent cryptogenic stroke compared to patients without a PFO who underwent a cryptogenic stroke under treatment with either aspirin or warfarin. But aspirin is more preferable (300 mg/d). However, it seems that the association between PFO and ASA confers an increased risk of recurrent stroke in medically treated patients who are less than 55 years of age. This subgroup of younger stroke patients may benefit from other treatments, such as the percutaneous closure of PFO or mini-invasive surgery to a lesser extent, but their efficacy and safety are not yet assessed by large randomized trials. However, we must also keep in mind that some stroke patients with PFO are psychologically attached to their PFO and prefer to close it.

Patent foramen ovale: does it play a role in the pathophysiology of migraine headache?

Migraine headaches have a high prevalence rate in the general population and account for significant morbidity, lost productivity, health care visits, and dollars spent. Increasingly, emerging data show a link between migraine headache, especially migraine headaches with aura, and patent foramen ovale (PFO). Closure of PFO as a cure for migraine headache is a tantalizing idea; this article examines the data supporting that possibility including studies showing improvement in migraine headache after PFO closure and case reports in which migraine headaches worsened after closure of an atrial septal defect.

Closure of a patent foramen ovale: effective therapy of migraine and occipital stroke

Whether stroke in a patient with migraine and patent foramen ovale (PFO) is due to PFO or migraine is difficult to decide. In a 33-year-old woman with migraine with aura, a visual field defect developed acutely. Neurological investigation revealed double vision when looking to the left and exaggerated patella tendon reflexes. Since then the patient complained about permanent visual impairment. CT- and MRI-scans of the brain showed a right occipital ischemic stroke. Intensive search for risk factors revealed cigarette smoking and chronic hypovolemia On transesophageal echocardiography an inter-atrial hypermobile septum and a PFO were detected. The patient underwent closure of the PFO by means of an Amplatzer PFO occluder nine weeks after the stroke. Since then she did not experience a further cerebrovascular event or migraine attack. This case shows that in a patient with PFO and migraine with aura, stroke may be attributable to migraine rather than to PFO. Occlusion of the PFO may reduce the frequency and intensity of migraine attacks.

Migraine: traditional or "innovative" treatment? A preliminary case-control study

The aim of this preliminary case-control study was to compare, in patients with migraine and PFO, transcatheter closure of PFO vs. medical treatments. Twelve patients were treated with antimigraine drugs and twelve underwent percutaneous transcatheter closure. All patients were followed-up for 12 months. Our preliminary results seem to confirm that, compared to medical treatment, PFO closure is by far more effective in reducing both frequency, duration and intensity of migraine attacks. Furthermore, the occurrence of prodromal aura is almost abolished.

Migraine headache relief after transcatheter closure of patent foramen ovale

OBJECTIVES

The purpose of this study was to determine the effects of transcatheter patent foramen ovale (PFO) closure on migraine frequency in patients with paradoxical cerebral embolism.

BACKGROUND

The prevalence of migraine headache is higher in cryptogenic stroke patients with PFO than in the general population. Previous studies have suggested that closure of the PFO may reduce migrainous symptoms.

METHODS

Between April 2001 and December 2003, 162 consecutive patients with paradoxical cerebral embolism underwent transcatheter PFO closure for prevention of recurrent cryptogenic stroke or transient ischemic attack. A one-year retrospective analysis of migraine symptoms before and after PFO closure was performed.

RESULTS

Active migraine was present in 35% (57 of 162) of patients, and 68% (39 of 57) experienced migrainous aura; 50 patients were available for analysis at one year. Complete resolution of migraine symptoms occurred in 56% (28 of 50) of patients, and 14% (7 of 50) of patients reported a significant (>or=50%) reduction in migraine frequency. Patients reported an 80% reduction in the mean number of migraine episodes per month after PFO closure (6.8 +/- 9.6 before closure vs. 1.4 +/- 3.4 after closure, p < 0.001). Results were independent of completeness of PFO closure at one year.

CONCLUSIONS

In patients with paradoxical cerebral embolism, migraine headaches are more frequent than in the general population, and transcatheter closure of the PFO results in complete resolution or marked reduction in frequency of migraine headache.

Association of interatrial shunts and migraine headaches

OBJECTIVES

To examine the relationship between patent foramen ovale (PFO) or atrial septal defect (ASD) with the incidence of migraine headache (MHA) and assess whether closure of the interatrial shunt in patients with MHA would result in improvement of MHA.

BACKGROUND

Migraine headache is present in 12% of adults and has been associated with interatrial communications. This study examined the relationship between PFO or ASD with the incidence of MHA and assessed whether closure of the interatrial shunt in patients with MHA would result in improvement of MHA.

METHODS

A sample of 89 (66 PFO/23 ASD) adult patients underwent transcatheter closure of an interatrial communication using the CardioSEAL (n = 22), Amplatzer PFO (n = 43), or the Amplatzer ASD (n = 24) device.

RESULTS

Before the procedure, MHA was present in 42% of patients (45% of patients with PFO and 30% of patients with ASD). At three months after the procedure, MHA disappeared completely in 75% of patients with MHA and aura and in 31% of patients with MHA without aura. Of the remaining patients, 40% had significant improvement (>or=2 grades by the Migraine Disability Assessment Questionnaire) of MHA.

CONCLUSIONS

Transcatheter closure of PFO or ASD results in complete resolution of MHA in 60% of patients (75% of patients with migraine and aura) and improvement in symptoms in 40% of the remaining patients. Interatrial communications may play a role in the etiology of MHA either through paradoxic embolism or humoral factors that escape degradation in bypassing the pulmonary circulation. A randomized trial is needed to determine whether transcatheter closure of interatrial shunts is an effective treatment for MHA.

Migraine and Cerebral White Matter Lesions

BACKGROUND

Patients with migraine are at an increased risk for white matter lesions, typically multiple, small, punctate hyperintensities in the deep or periventricular white matter, best observed on magnetic resonance imaging utilizing T2-weighted or FLAIR sequences. The underlying pathogenesis of white matter lesions in migraineurs is unknown, and the lesions are usually nonspecific and of unclear clinical significance.

REVIEW SUMMARY

Often the presence of white matter lesions causes uncertainty for physicians and anxiety for patients and may lead to a variety of diagnostic tests and treatments. Occasionally, white matter lesions may represent a secondary cause for headaches such as CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy). CADASIL is underrecognized and underdiagnosed; it should be suggested by (i) 1 or more of recurrent subcortical ischemic strokes (especially before age 60 and in the absence of vascular risk factors), migraine (especially with aura, including atypical or prolonged auras) and/or early cognitive decline or subcortical dementia; (ii) bilateral, multifocal, T2/FLAIR hyperintensities in the deep white matter and periventricular white matter with lesions involving the anterior temporal pole, external capsule, basal ganglia, and/or pons; and (iii) an autosomal-dominant family history of migraine, early-onset stroke, or dementia. The clinical spectrum of CADASIL is broad, and there is a poor genotype-phenotype correlation. In certain individuals or families, migraine may be the only clinical manifestation.

CONCLUSIONS

While the prevalence of nonspecific white matter lesions in migraineurs is increased, the white matter lesions may occasionally represent a secondary cause for headache such as CADASIL. Greater awareness of the unique clinical, neuroimaging, and pathologic features, as well as the availability of diagnostic genetic testing, should enhance the recognition and diagnosis of this fascinating condition.

Inheritance of persistent foramen ovale and atrial septal defects and the relation to familial migraine with aura

OBJECTIVE

To determine whether smaller atrial shunts (large persistent foramen ovale (PFO) and small atrial septal defect (ASD)) are inherited and whether this has a role in the inheritance of migraine with aura.

METHODS

Contrast echocardiography was used to detect atrial shunts in 71 relatives of 20 probands with a significantly sized atrial shunt (large PFO or ASD). Four families with three generations, 14 families with two generations, and two sibships were studied. The contrast echocardiograms were performed blind to history of migraine. A consultant neurologist, who was blinded to cardiac findings, categorised migraine symptoms in subjects.

RESULTS

The occurrence of atrial shunts was consistent with autosomal dominant inheritance. Usually shunts were large PFOs, but in some cases they were ASDs. There was also evidence that inheritance of more complex congenital heart disease may be related to the inheritance of PFOs. When the proband had migraine with aura and an atrial shunt, 15 of the 21(71.4%) first degree relatives with a significant right to left shunt also had migraine with aura compared with three of 14 (21.4%) without a significant shunt (p < 0.02).

CONCLUSIONS

There is dominant inheritance of atrial shunts. This is linked to inheritance of migraine with aura in some families.

Estrogens, migraine, and stroke

Epidemiological studies suggest the existence of close but complex relationships between estrogens, migraine, and stroke in women before menopause. Migraine, particularly without aura, is strongly influenced by estrogens as illustrated by the frequency of onset at puberty, of menstrual migraine, and of improvement during pregnancy. Migraine, particularly with aura, is a risk factor for ischemic stroke with a relative risk of 3, further increased by tobacco smoking and oral contraceptive use. The pathophysiological mechanism underlying these close relationships remains unknown. In practice, given the very low absolute risk of stroke in young women, there is no systematic contraindication to oral contraceptive use in young female migraineurs but rather a firm recommendation for no smoking and for the use of low-estrogen-content pills or progestogens only, particularly in migraine with aura.

Percutaneous closure of patent foramen ovale reduces the frequency of migraine attacks

Among 215 patients referred for percutaneous closure of patent foramen ovale (PFO) after presumed paradoxical embolism, we assessed the prevalence of migraine. In the year prior to PFO closure, 48 (22%) patients had migraine, twice the expected prevalence of 10 to 12% in the general European population. In patients with migraine with aura, percutaneous PFO closure reduced the frequency of migraine attacks by 54% (1.2 +/- 0.8 vs 0.6 +/- 0.8 per month; p = 0.001) and in patients with migraine without aura by 62% (1.2 +/- 0.7 vs 0.4 +/- 0.4 per month; p = 0.006). PFO closure did not have an effect on headache frequency in patients with nonmigraine headaches (1.4 +/- 0.9 vs 1.0 +/- 0.9 per month; p = NS).

Headache and the risk of stroke

Several studies have suggested that migraine is a risk factor for stroke. The association between migraine and the risk of stroke has been observed most often among premenopausal women but also in some studies among men. The association may be stronger among women who smoke and among women using oral contraceptives compared with nonsmokers and nonusers. Classic migraine with aura may be a more powerful predictor of stroke than common migraine without aura. Findings of a recent population-based study suggest that subclinical brain lesions are more common among migraine patients, particularly among those with aura, than among the control subjects. Two cohort studies have shown that chronic non-specific headache also is related to increased stroke risk. The effect of treatment of migraine and other types of headache on the risk of stroke is not known. Even though the relative risk of stroke may be fairly high among migraine patients, the absolute risk is usually low due to low baseline risk among young people.

Percutaneous transcatheter patent foramen ovale closure using the right internal jugular venous approach

Percutaneous transcatheter closure of a patent foramen ovale (PFO) is a therapeutic option in patients with paradoxical embolism. For patients in whom PFO closure is indicated when a femoral venous approach is not possible, we describe the successful closure of two PFOs using the right internal jugular venous approach.

Controlled Contrast Transcranial Doppler and Arterial Blood Gas Analysis to Quantify Shunt Through Patent Foramen Ovale

Background and Purpose— A right-to-left shunt can be identified by contrast transcranial Doppler ultrasonography (c-TCD) at rest and/or after a Valsalva maneuver (VM) or by arterial blood gas (ABG) measurement. We assessed the influence of controlled strain pressures and durations during VM on the right-to-left passage of microbubbles, on which depends the shunt classification by c-TCD, and correlated it with the right-to-left shunt evaluation by ABG measurements in stroke patients with patent foramen ovale (PFO).

Methods— We evaluated 40 stroke patients with transesophageal echocardiography–documented PFO. The microbubbles were recorded with TCD at rest and after 4 different VM conditions with controlled duration and target strain pressures (duration in seconds and pressure in cm H 2 O, respectively): V5-20, V10-20, V5-40, and V10-40. The ABG analysis was performed after pure oxygen breathing in 34 patients, and the shunt was calculated as percentage of cardiac output.

Results— Among all VM conditions, V5-40 and V10-40 yielded the greatest median number of microbubbles (84 and 95, respectively; P <0.01). A significantly larger number of microbubbles were detected in V5-40 than in V5-20 ( P <0.001) and in V10-40 than in V10-20 ( P <0.01). ABG was not sensitive enough to detect a shunt in 31 patients.

Conclusions— The increase of VM expiratory pressure magnifies the number of microbubbles irrespective of the strain duration. Because the right-to-left shunt classification in PFO is based on the number of microbubbles, a controlled VM pressure is advised for a reproducible shunt assessment. The ABG measurement is not sensitive enough for shunt assessment in stroke patients with PFO.

Headaches due to vascular disorders

The association between stroke and headache is complex, ranging from highly nonspecific, wherein headache is largely irrelevant to diagnosis and therapeutic management, to highly specific and even causative. In short, acute headache may accompany the acute stroke process, chronically complicate stroke, or, in rare instances, serve as the primary cause of stroke. With the first instance, the incidence of acute headache is highly dependent on the stroke sub-type and etiology. In this article, the headaches accompanying or causing acute stroke are addressed in some detail.

Basilar and Middle Cerebral Artery Reactivity in Patients With Migraine

BACKGROUND

Migraine has been reported as a possible risk factor for ischemic stroke. The mechanisms underlying this association are unknown.

OBJECTIVES

To evaluate cerebrovascular reactivity to hypercapnia in the anterior and posterior circulation of patients with migraine, as reduced cerebrovascular reactivity is associated with a predisposition to stroke in various clinical conditions.

METHODS

Using transcranial Doppler ultrasonography, changes in flow velocity during apnea were measured in both middle cerebral arteries and in the basilar artery of 15 control subjects and 30 patients with migraine (15 with aura and 15 without aura) during an attack-free period. Cerebrovascular reactivity was evaluated using the breath-holding index, which is calculated by dividing the percent increase in mean flow velocity recorded during a breath-holding episode by its duration (in seconds) after a normal inspiration.

RESULTS

Vascular reactivity in the middle cerebral arteries was similar in patients and controls and significantly lower in the basilar artery of patients with migraine with aura compared with the other 2 groups (P <.0001).

CONCLUSIONS

These findings show that in patients with migraine with aura, there is an impairment in the adaptive cerebral hemodynamic mechanisms in the posterior circulation. This fact could have pathogenetic implications since the association between migraine and stroke frequently regards patients with migraine with aura, and cerebral infarcts occur more commonly in the vertebrobasilar district.

Migraine with aura related to the percutaneous closure of an atrial septal defect

We report a case of a 31-year-old woman who presented migraine attacks with aura within the 48 hr after transcatheter closure of an atrial septal defect with the Amplatzer septal occluder device. The migraine attacks persisted for 3 months, and all examinations performed to rule out a thromboembolic origin of migraine were negative.

Transient global amnesia in a young adult with cyanotic heart disease

The etiology of transient global amnesia is poorly understood, particularly in children and young adults. Transient global amnesia may follow a wide range of precipitating events. Proposed causes have included vascular event, seizure, and migraine. A young man with cyanotic congenital heart disease experienced an episode of transient global amnesia in the setting of polycythemia. Differential diagnosis of acute confusional episodes in children should include transient global amnesia, as well as confusional migraine, and should include evaluation for underlying coagulation abnormalities and polycythemia.

Prevalence of atrial septal aneurysm in patients with migraine: an echocardiographic study

OBJECTIVE

To evaluate the prevalence of atrial septal aneurysm in patients with migraine.

BACKGROUND

Migraine has long been considered a risk factor for stroke. Atrial septal aneurysm is often observed in young patients with ischemic stroke and is frequently associated with other conditions potentially leading to embolism.

METHODS

We performed a transthoracic echocardiogram in 90 consecutive patients (65 women and 25 men; mean age, 35.3 years [standard deviation, 9]) with migraine but free from cerebral and cardiovascular disease and in 53 control subjects (37 women and 16 men; mean age, 34 years [standard deviation, 10]). The diagnosis of atrial septal aneurysm was performed according to Olivares-Reyes criteria. A transesophageal echocardiogram also was performed in 75 patients with migraine (83.3%).

RESULTS

The prevalence of isolated atrial septal aneurysm was higher in patients with migraine with aura (28.5%) than in patients with migraine without aura (3.6%) (P <.005) or in control subjects (1.9%) (P <.005).

CONCLUSIONS

Our data suggest a role of atrial septal aneurysm in the genesis of aura in patients with migraine.

Transformation into daily migraine with aura following transcutaneous atrial septal defect closure

A link between migraine with aura and cardiac right-to-left shunting has been previously reported. Abortion or decreased frequency of migraine with aura attacks after atrial septal defect closure has been reported in the literature. We report the first case of transformation of migraine with aura into a daily pattern after atrial septal defect closure. A 48-year-old male who had been suffering from rather infrequent attacks of migraine with sensory and visual aura underwent transcutaneous closure of an atrial septal defect. His migraine attacks changed into a daily pattern the day following the procedure and remained so for 6 months. This change in pattern may be related to a changed intra-atrial pressure after the closure or some other unknown factor.

Factor V Leiden and prothrombin gene mutation may predispose to paradoxical embolism in subjects with patent foramen ovale

The role of paradoxical embolism through patent foramen ovale as a mechanism of cryptogenic stroke is controversial. If a venous source of emboli is relevant, prothrombotic states should be associated with patent foramen ovale and cryptogenic stroke. We assessed the occurrence of several prothrombotic states (factor V Leiden, prothrombin G20210A, deficiencies in protein S, protein C and antithrombin, lupus anticoagulant, anticardiolipin antibodies, elevated factor VIII, resistance to activated protein C) and classical risk factors for venous thrombosis in 57 adult patients with cryptogenic stroke and patent foramen ovale and in 104 matched controls. Prothrombotic states [odds ratio (OR) 2.8; 95% confidence interval (CI), 1.2-6.5; P = 0.021], migraine with aura (OR 4.4; 95% CI 1.8-10.8; P = 0.001) and classical risk factors for venous thrombosis (OR 2.5; 95% CI 1.1-5.7; P = 0.037) were independent risk factors for cryptogenic stroke. In particular factor V Leiden or prothrombin G20210A associated with cryptogenic stroke (P = 0.022) whereas other coagulation abnormalities did not (P = 0.140). Among the patients with prothrombotic states, Valsalva manoeuvre was common at onset of stroke. Our results support the possibility of paradoxical embolism behind strokes in patients with patent foramen ovale.

Transcranial Doppler and risk of recurrence in patients with stroke and patent foramen ovale

The importance of patent foramen ovale (PFO) in stroke of unknown cause remains disputed, as PFO may be present in up to 20% of normal people and in a high proportion of patients with non-vascular disorders. Recent evidence suggests that the amount of right-to-left shunt (RLS) may be the crucial factor for stroke occurrence and relapse. The aim of the study was to assess predictors of recurrence in PFO-related stroke patients with particular emphasis on amount of shunting. Patients less than 61 years old who had been admitted for a PFO-related stroke within the previous 5 years, were re-evaluated on a follow-up visit. The clinical syndrome, residual disability, vascular risk factors and number of relapses as the index event were assessed. RLS sizing was semi-quantitatively performed with saline-enhanced transcranial Doppler (TCD), by assuming a cut-off of more or less 10 bubbles recorded in the cerebral vessels as a criterion to discriminate large versus small shunt, respectively. Thereafter patients were prospectively followed-up for a median time of 23 months. Total follow-up was 61 months. Fifty-nine patients (M/F = 23/36, mean age 43 +/- 13) were studied. Overall there were 23 relapses in 13 patients. The amount of shunting was the only significant independent variable associated with relapse: at the end of the follow-up period the recurrence rate was 0.66 and 8.2% per patient per year in patients with small and large shunt, respectively. This difference was statistically significant (chi2 = 10.39, P = 0.0012; OR 17.05, 95% CI 2.10-755.22). In patients with PFO-related stroke, the amount of RLS as assessed with TCD is the only independent predictor of relapse. PFO sizing is mandatory in patients with PFO.

Clinical impact of patent foramen ovale diagnosis with transcranial Doppler

The role of patent foramen ovale (PFO) in cryptogenic stroke is still debated, but from recent follow-up studies it seems that the amount of right-to-left shunt (RLS) and the association with atrial septal aneurysm (ASA) are major determinants of stroke recurrence. PFO and RLS through the atrial chambers have been recently studied in a number of conditions not or marginally related to cerebrovascular disease. Historically the first studies addressed the presence of RLS in scuba divers as a possible abnormality related to decompression sickness (DS) of unknown aetiology. Despite initial debate there is now robust evidence to claim that patency of foramen ovale increases the risk of developing DS by two and half to four times. Patients with PFO-related DS tend to have early occurrence of symptoms after surfacing and a clinical presentation that indicates brain or upper cervical spinal cord involvement. Recent reports suggest that divers with hemodynamically significant RLS may have an increased risk of developing clinically asymptomatic multiple brain lesions. PFO has been found in patients suffering from migraine with aura with approximately the same frequency as that encountered in cryptogenic stroke patients. This finding has prompted speculations on the possible role of RLS in increasing the stroke risk in migraineurs and in the pathophysiology of the aura. Recent reports showing that migraine with aura is dramatically improved after transcatheter closure of PFO suggest that migraine with aura may indeed be triggered by humoral factors that reach the brain by escaping the pulmonary filter. A RLS is involved in a rare condition known as platypnea-orthodeoxia and perhaps underlies an increased risk of cerebral complications after major orthopedic surgery. Valsalva-like activities often precede the occurrence of attacks of transient global amnesia (TGA) and abnormalities consistent with hypoperfusion of deep limbic structures have been reported during a typical TGA episode. This had raised the hypothesis that TGA may be triggered by paradoxical embolism of platelets aggregates in the posterior circulation, but the search for an increased frequency of PFO in TGA patients has yielded conflicting results. Conditions that determine an increase in pulmonary pressure may facilitate the opening of the virtual interatrial valve and thus promoting shunting of blood to the left heart chambers which in turn might contribute to further desaturation of arterial blood. It is therefore not surprising that RLS has been found in 70% of patients with chronic obstructive pulmonary disease and increased pulmonary pressure and in the same proportion of patients with obstructive sleep apnoea, a condition that ultimately may result in pulmonary hypertension. In conclusion, from the evidence gathered so far the picture is emerging of an important role of PFO in a number of non-stroke conditions, either as causative factor or as associated condition predisposing to complications. The availability of simple diagnostic techniques such as transcranial Doppler (TCD) to assess RLS will undoubtedly contribute a great deal of knowledge on the relevance in medicine of this hitherto neglected condition.